Impact of Pharmacovigilance Interventions Targeting Fluoroquinolones on Antibiotic Use in the Netherlands and the United Kingdom.

Purpose: Fluoroquinolones are antibiotics associated with adverse events that prompted the European Medicines Agency to implement risk minimization measures (RMMs) in 2018/19 and 2020. Our aim is to assess the RMMs' impact on antibiotic prescriptions in primary care during 2014-2023.

Methods: We assessed antibiotic prescriptions using CPRD GOLD (the United Kingdom, UK) and PHARMO (the Netherlands, NL). Prescriptions were assessed for fluoroquinolones and alternative antibiotics. The impact of RMMs on prescribing was assessed with interrupted time series (ITS) using monthly prescription rates per 10 000 person-years (MPTPY).

Results: Between 2014 and 2023, we identified cohorts of 4.0 (UK) and 0.9 million (NL) antibiotic users. Fluoroquinolones were prescribed to initiate 1.5% (UK) to 5.8% (NL) of the treatment episodes. Fluoroquinolone prescribing before the RMMs slowly decreased in the UK and was stable in the NL. The 2018/19 RMMs were associated with a steady downward post-RMMs trend in incident use of fluoroquinolones (MPTPY -0.7 [UK] and -0.8 [NL]) and opposite changes after 2020 RMMs (MPTPY 0.6 [UK] and 1.8 [NL]). The 2018/2019 RMMs were linked with increasing trends for other antibacterials (J01XX) in both countries and other beta-lactam antibacterials in the UK, but most antibiotics had decreasing trends post-RMMs in both countries. After the 2020 RMMs, some antibiotic groups showed upward trends.

Conclusion: The risk minimization measures in 2018/2019 were associated with a moderate decrease in fluoroquinolone prescribing, with no further decrease after 2020 RMMs. There was no sustained increase in other antibiotic prescribing, suggesting that overprescribing was negligible as an unintended impact of RMMs.